Answer:
Working backward method
Step-by-step explanation:
The working backward method is some sort of "mental trick" that can help us solve a problem. Imagine hat you are in the same problem as Marcus, but you are no expert in the tool shed building business and really dont know how to start building it.
What the working backward method tells you is that, instead of (over)thinking the first step, imagine that you have already finish the project and start going backwards until, eventually, you might find the key (answer, problem) you are looking for and actually start building the tool shed:
In the way you will probably find out what materials you would need, how the tool shed would look like (blueprints) and might just see how to make step 1, then step 2, and so on.
Hope this helps!